Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
Division of General Internal Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
Am J Physiol Lung Cell Mol Physiol. 2021 Nov 1;321(5):L837-L843. doi: 10.1152/ajplung.00260.2021. Epub 2021 Sep 8.
Bronchoalveolar lavage (BAL) samples from Severe Asthma Research Program (SARP) patients display suppression of a module of genes involved in cAMP-signaling pathways (BALcAMP) correlating with severity, therapy, and macrophage constituency. We sought to establish if gene expression changes were specific to macrophages and compared gene expression trends from multiple sources. Datasets included single-cell RNA sequencing (scRNA-seq) from lung specimens including a fatal exacerbation of severe Asthma COPD Overlap Syndrome (ACOS) after intense therapy and controls without lung disease, bulk RNA sequencing from cultured macrophage (THP-1) cells after acute or prolonged β-agonist exposure, SARP datasets, and data from the Immune Modulators of Severe Asthma (IMSA) cohort. THP monocytes suppressed BALcAMP network gene expression after prolonged relative to acute β-agonist exposure, corroborating SARP observations. scRNA-seq from healthy and diseased lung tissue revealed 13 cell populations enriched for macrophages. In severe ACOS, BALcAMP gene network expression scores were decreased in many cell populations, most significantly for macrophage populations ( < 3.9e-111). Natural killer (NK) cells and type II alveolar epithelial cells displayed less robust network suppression ( < 9.2e-8). Alveolar macrophages displayed the most numerous individual genes affected and the highest amplitude of modulation. Key BALcAMP genes demonstrate significantly decreased expression in severe asthmatics in the IMSA cohort. We conclude that suppression of the BALcAMP gene module identified from SARP BAL samples is validated in the IMSA patient cohort with physiological parallels observed in a monocytic cell line and in a severe ACOS patient sample with effects preferentially localizing to macrophages.
支气管肺泡灌洗液(BAL)样本来自严重哮喘研究计划(SARP)患者,显示与严重程度、治疗和巨噬细胞组成相关的 cAMP 信号通路相关基因模块受到抑制(BALcAMP)。我们试图确定基因表达变化是否特定于巨噬细胞,并比较来自多个来源的基因表达趋势。数据集包括来自肺标本的单细胞 RNA 测序(scRNA-seq),包括经过强化治疗后的严重哮喘 COPD 重叠综合征(ACOS)的致命恶化和无肺部疾病的对照,急性或长期β激动剂暴露后培养的巨噬细胞(THP-1)细胞的批量 RNA 测序,SARP 数据集以及严重哮喘免疫调节剂(IMSA)队列的数据。THP 单核细胞在急性β激动剂暴露后长时间暴露时抑制 BALcAMP 网络基因表达,这与 SARP 观察结果一致。来自健康和患病肺组织的 scRNA-seq 揭示了 13 个富含巨噬细胞的细胞群。在严重 ACOS 中,许多细胞群的 BALcAMP 基因网络表达评分降低,巨噬细胞群降低最显著(<3.9e-111)。自然杀伤(NK)细胞和 II 型肺泡上皮细胞的网络抑制作用较弱(<9.2e-8)。肺泡巨噬细胞显示受影响的个体基因数量最多,调节幅度最大。关键的 BALcAMP 基因在 IMSA 队列中的严重哮喘患者中表达显著降低。我们得出结论,从 SARP BAL 样本中鉴定出的 BALcAMP 基因模块的抑制在 IMSA 患者队列中得到验证,在单核细胞系和严重 ACOS 患者样本中观察到生理相似性,其影响优先定位于巨噬细胞。